Printing press gripper mechanism



June 1945. E. w] WORTHINGTON 2,373,523

PRINTING PRESS GRIPPER MECHANISM Filed Feb. 18, 1943 Pa'tented June 19,: 1945 PRINTING PRESS GRIPPER MECHANISM Emory W. Worthington, Chicago, Ill., assignor to The Goss Printing Press Company, Chicago, Ill.,. a corporation of Illinois Application February 18, 1943, Serial No. 476,261

4 Claims.

The present invention relates-to new and useful improvements in sheet gripping devices, and more particularly to improved spring grippers or folding jaws especially adapted for use in printing presses.

Objects and advantages of the invention will be set forth in part hereafter, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described;

The accompanying drawing, referred to herein and constitutinga part hereof, illustrates embodiments of the invention, and, together with the description, serve to explain the principles of the invention.

Fig. 1 is a fragmentary vertical section through a cylinder to whichthe improved gripper is applied as embodied in one form of the invention.

Fig. 2 is a view showing a modified construction of the shaft and gripping finger of the type illustrated in Fig, 1.

Fig. 3 is a View similar to Fig. 1, showing another embodiment of the invention.

Fig. 4 is a view similar to Fig. 2, showing a modification in the construction of the shaft and gripping finger of the type illustrated in Fig. 3.

The invention is directed to providing novel and improved sheet gripping instrumentalities, operating by a gripping or clamping action, either medianly or on the edge, of a sheet or group of sheets, as in feeding or folding; and in its main features being capacitated for use either in a' otherwise structurally desirable.

found, for example, that in the mounting of the gripping finger mechanism or a folding jaw ping or clamping members or jaws mounted on a shaft rocked through a-small angle by cam mechanism or the like carriedby the cylinder to effect the opening and closing of the gripper mechanism.

In prior patents, No. 1,843,754, dated February 2, 1932, and No.. 1,895,124, dated January 24, 1933, the latter reissued May 28, 1935, under Reissue No. 19,591, there are disclosed gripper mechanisms of this type in which single leaf spring and laminated leaf spring grippers are provided for coaction with a stationary gripper or grippers formed or provided upon one of the walls of the slot in the cylinder. Such gripper mechanisms, particularly when equipped with laminated leaf spring grippers, have been found highly efficient for use in sheet transfer gripping and folding operations because of their elastic gripping actions, great durability, capability of firmly gripping commodities of different thicknesses, and in enabling high speed folding operations to be carried out.

Grippermechanisms of this type, however, while highly eflicient, as stated, are open to certain inherent practical objections, particularly in their use on small cylinders and when operated. by cam mechanisms of a certain kind, which are It has been resilient grippers on an actuating rock shaft operated by cams inclosed in the wheel, shock vvibrations are caused which are transmitted to and tend to cause jumping 01 the cams and undue Wear and tear on the cam roller surfaces. Another objection to this prior type of gripper mechanism is that the length of the resilient grippers, the radius of action of the moving grippers and the diameter of the cam path cannot be readily designed and regulated to suit different conditions of service or different sizes of cylinders. Furthermore, in the use of resilient grippers on the shaft the formation of indentations, corrugations and the like in the gripped sheets, when desired, cannot be readily made.

The present invention has for its main object the provision of a novel gripper mechanism which overcomes these and other minor objection to gripper mechanisms of the aforesaid prior type and which possesses other substantial and important advantages.

In its structural organization the present in- V vention provides a gripper mechanism in which the stationary grippers are in the form of laminated leaf spring members mounted on the cylinder, and in which the movable grippers are in the form of non-resilient fingers solidily mounted on the actuating shaft, whereby all vibratory shock ment of the resilient gripping members and gripare effectually overcome and additional advantages secured.

Referring now more particularly to the embodiment of the invention shown in Fig. 1, l indicates a portion of a cylinder structure which is provided with a radial slot Ii opening through its rim and with a. recess i2 also opening through its rim and communicating with the slot at one side thereof. This recess has an inclined bottom seat wall I! extending between the slot and periphery of the rim and tangentially to the latter. Suitably secured in the recess and closing the same except at its side intersecting the slot is a recess closing and gripper supporting block Id. The block I is shaped at its base to conform to the seat wall l3 on which it rests and at its outer surface to conform to the curvature of the outer surface of the cylinder.

The side of the block which faces the slot Ii terminates short thereof and lies adjacent thereto but within the recess. Said side of the block has an outer face i5 and an inwardly projecting shoulder It at the base thereof, the face i5 and inner face of the shoulder being disposed in parallel planes and both inclined outwardly toward the periphery of the cylinder at an angle thereto and to the slot I I. Mounted on the block is a laminated leaf spring ripping member l'l having an inner end or butt portion l8 abutting against the. seat face i3 and shoulder i6 and having an outer free end portion whose tip it constitutes a gripping jaw. A clamp plate 20 bears on the relatively outer face of this gripping member and a machine bolt 21 passes therethrough and through the gripping member and into the shoulder and clamps the inner end or butt portion of said member against the shoulder IS.

The plate 20 bears at its inner end on the seat face and free portion of the member I! out-- wardly beyond the shoulder it, but is of less length than the member l1 and terminates short of the outer end thereof, leaving the latter projecting to form the jaw is which is located adjacent to the periphery of the cylinder and exposed to the slot through the adjacent side of the reas'rasas ping fingers whereby the other disadvantages of the prior type of gripper mechanism referred to.

toward the member ii to grip an inserted sheet or sheets 3| between it and the jaw IQ of the member l1 and when rocked away from the member II to effect the release ofthe sheet in an obvious manner. v

It will be observed that 'the-inclination of the gripper l1 and movement of the gripper 24 is such that the jaws l9 and 21 when in gripping position will be parallel witheach other and grip the sheet in a plane parallel'with the slot It so that the sheet will bequickly and firmly gripped in a vise-like manner and quickly released through small movements of the gripper 24, allowing the action to bevery rapidly carried out. Another advantage incident to the described mounting of the gripper i1 is that its vibrations are dampened and sustained by the cylinder which absorbs them' sothat no shocks are transmitted to the shaft or its operating cam mechanism to cause injury to or undue wear and tear on the latter. The gripping mechanism may, therefore, be used in high speed actions without the production of dynamic and vibration effects liable to damage any of the parts of the apparatus. Furthermore, the novel arrangement and mode of mounting the resilient grippers permits of the use of grippers of a length best suited for any sized cylinder and without requiring difing and the transmission of shocks,- jars and vibrations to the shaft and its cam operating mechanism.

cess. The free portion of the spring member i1 is backed and limited in its movement toward the slot, but is free to yield into the space between it and the face 15 of the block l4. Preferably the free portion of the spring member I1 is preloaded or placed under initial spring tension, as

by forming the plate 20 with a recess 22 and a projecting portion 23 holding the member slightly flexed so that it will give an instantaneous preliminary pressure on the gripped sheet immediately the gripper i9 engages the sheet.

A plurality of such leaf spring grippers l1 may be mounted side by side or at spaced intervals on the cylinder and a movable non-resilient gripper 24 is provided on a rock shaft 25 for coaction with each gripper IT. The shaft 25 is mounted on the cylinder within the slot 1 I. The shaft is adapted to be periodically rocked through asmall angle, in the usual manner, by any standard, well known or other suitable mechanism (not shown) mounted within the cylinder so as to move the grippers 24 toward and from the grippers l'I. Each group of these grippers 24, as shown in Fig. 1, comprises a gripping finger 26 having a gripping jaw 21 and secured by asplit hub 28 and a machine bolt or screw 29, to the shaft, so that it will be firmly and solidly mounted on the shaft. The jaw 21 is adapted when rocked It'is possible with this novel construction of gripping mechanism to use, an assembly of the resilient grippers and mount the same as a unit "or in a plurality of sections entirely across the cylinder, thus doing away with the previous troublesome practice of mounting individual resilient grippers in spaced relation on the rock shaft and the necessity of adjusting them and keeping them adjusted. .Su'ch an assembly may be applied and removed for replacements, repairs and other purposes without the necessity, as heretofore, of dismantling the rock shaft and parts thereon,.and with a great saving of time and labor in effecting these operations. 1

By providing gripping fingers of the type disclosed it is also possible to machine the grippers and shaft in a single piece so as to allow a very strong section in the gripping members. Such a construction is disclosed in Fig. 2 in which the shaft 25' is shown as provided with a gripper 24' at its end remote from the slot is formed with an inclined seat wall' or face I! and a shoulder l3, said seat wall being inclined at an obtuse angle to the slot and on a line tangential to the periphery screw II. The block H has an inner end face conforming to the shoulder 13 and an outer curved face conforming to the curvature of the periphery of the cylinder and is of less length than the gripper i'l' so as to close the portion of the recess beyond the gripper between the shoulder l3 and free end IQ of the gripper, leaving said gripper end is exposed to the slot II at the inner end of the-recess and at the surface of the cylinder adjacent thereto. The inner face of the block is formed with a recess 22' and a projection 23 to prelcad the spring or to hold it under initial tension. The gripper i1 thus extends frcm its butt end at an angle toward the periphery of the cylinder and in one direction circumferentially of the cylinder with its free end or jaw portion i8 disposed in a plane coincident with that of the adjacent portion of the surface of the cylinder and circumferentially thereof.

Mounted in the slot I4 is a rock shaft 25', similar to the shaft 25, on which is mounted a nonresilient gripper 24 having a gripping'finger 26' terminating in a gripping jaw 21' and secured to the shaft by a split hub 28' and machine bolt or screw 29'. The finger 26', as shown, extends outward in the slot beyond the shaft and its jaw 21' lies just beyond the surface of the cylinder and projects in the opposite direction to and normally overlies the jaw is of the gripper H. The

action of the parts in this embodiment is the same as that of the embodiment disclosed in Fig. 1 except that the sheet 30' fed to the jaws i9 21' in the direction of rotation of the cylinder is clamped flatly and in a vise-like manner between a resilient jaw and a non-resilient jaw at the surface of the cylinder on a line "substantially flush with such surface. As in the structure disclosed in Fig. 1, the resilient gripper is mounted on the cylinder which sustains and dampens all vibration shocksand coacts with a solid non-resilient grip" per on the actuating rock shaft which resists torque strains and prevents transmission of vibration shocks to the shaft and through the shaft to its actuating cam mechanism.

Grippers of the type employed in Fig. 3 may be formed integral with the shaft, as shown by the gripper 24 and shaft 25' in Fig. 4, in the same manner as that explained with reference to Fig. 2.

The invention in its broader aspects is not limited to the specific mechanisms shown and described, but departures maybe made therefrom within the scope of the appended claims without:

departing from the principles of the invention and without sacrificing its chief advantages.

Having thus described my invention, I claim:

1. A gripping mechanism includin in combination a cylinder having a radial slot opening through its periphery and a recess at one side of said slot, a preloaded-laminated spring gripping member having relatively stiff and flexible butt and gripping jaw ends, fastening means including a block closing the recess except at its side facing the slot and securing the butt and of said gripping member to the cylinder and leaving its jaw end free and at an angle to the slot and so as to be pressed to a gripping position substantially parallel with the slot, a rock shaft in the slot, and a non-resilient gripping finger mounted on the shaft for movement toward and from the gripping member and having a jaw arranged to clamp an inserted sheet against the gripping jaw of said member in a direction lo radially of the cylinder.

2. A gripping mechanism including in combination a cylinder having a radial slot opening through its periphery and a recess at one side of said slot, a laminated spring gripping member 5 having relatively stiff andflexible butt and gripping jaw ends, fastening means including a block -csing a portion of the recess circumferentially of the cylinder beyond said side'of the slot so as to leave a portion of the recess open at its side facing the slot and securing the butt end of said gripping member within the recess with its free end disposed at an angle to the radial line of the slot and so as to adapt it to be pressed in the direction of the recess to a gripping position, a rock shaft mounted in the slot, and a non-resilient gripping member mounted on the shaft for cooperation with 'the resilient gripping member and having a finger extending outwardly toward the circumference of the cylinder and terminating in a gripping law bent laterally in a direction toward the recess and movablein such direction to clamp an inserted sheet against the gripp g law of the resilient gripping member.

3. A gripping mechanism including in combination a cylinder having a radial slot opening through its periphery and a recess at one side of said slot, a Laminated spring gripping member having relatively stiff and flexible butt and gripping jaw ends, fastening means including a block 40 closing the recess except at its side facing the slot and securing the butt end of said gripping member to the cylinder and leaving its jaw end free and arranged adjacent to the periphery of the cylinder at such an angle to the slot as to adapt it to be pressed to a gripping position within the open side of the recess, a rock shaft in the slot, and a non-resilient gripping finger m unted on the shaft for movement toward and from the spring gripping member and having a jaw operative in one direction of movement to press and tension the spring member and to clamp an inserted sheet against the gripping jaw of said member and operative in its other direction of movement to relieve the spring. member from pressure and permit it to return by its resiliency to nonripping position.

4. A gripping device including in combination a cylinder having a peripheral portion and provided with a dial slot and a recess at one side of the slot, a resilient leaf spring gripping member,

fastening means including a block closing a portion of the recess and fixing the spring member at one end to the cylinder leaving its opposite end free and in the form of a gripping jaw normally exposed in the recess at the periphery of the cyl- 'inder, a rock shaft mounted within the slot, and a non-resilient gripping finger mounted on the shaft for movement toward and from the spring gripping member and arranged to clamp an inserted sheet against the gripping jaw of said member in the direction of rotation of the cylinder.

. EMORY W. WORTHING'I'ON. 

